Obesity is excess body weight for a particular age, sex and height as a consequence of imbalance between energy intake and energy expenditure. The primary cause of obesity is either due to overeating, inadequate exercise or eating disorder, some genetic disorders, underlying illness (e.g., hypothyroidism), certain medications, sedentary lifestyle, a high glycemic diet (i.e., a diet that consists of meals that give high post-prandial blood sugar) weight cycling (caused by repeated attempts to lose weight by dieting, eating disorders), stress and insufficient sleep.
During the past 20 years, obesity among adults has risen significantly in the United States. The latest data from the National Center for Health Statistics show that 30 percent of U.S. adults of 20 years of age and older, i.e. over 60 million people, are obese. The percentage of young people who are overweight has more than tripled since 1980. More than 16% of the children and teens aged 6-19 years, that is over 9 million young people, are considered overweight. Although, the US national health objectives for the year 2010 is to reduce the prevalence of obesity among adults to less than 15%, current data indicate that the situation is worsening rather than improving (http://www.cdc.gov/nchs/products/pubs/pubd/hestats/overweight/overwght_adult_03.htm). Obesity in Europe was recognized as a serious problem, with up to 27% of men, 38% of women and 3 million children are clinically obese (http://ec.europa.eu/health/ph_determinants/life_style/nutrition/green-papmutritiongp_c0183_en.pdt). The obesity was not limited to developed countries, but it was rapidly becoming a problem in developing countries as well.
As per World Health Organization's (WHO) latest projections, approximately 1.6 billion adults (age 15+) were overweight and at least 400 million adults were obese globally in 2005. WHO further projects that by 2015, approximately 2.3 billion adults will be overweight and more than 700 million will be obese (WHO's fact sheet No. 311, September 2006, http://www.who.int/mediacentre/factsheets/fs311/en/index.html).
Recent studies have shown that approximately a third of variance in adult body weights results from genetic influences. Leptin, an adipocyte and placenta-derived circulating protein, regulates the magnitude of fat stores in the body leading to obesity. Gastrointestinal peptides, neurotransmitters and adipose tissue may also have an etiologic role in obesity. Obesity and adipose tissue expansion increase the risk of hypertension, type 2 diabetes, arthritis, elevated cholesterol, cancer and serious hormonal imbalances in women, leading to sterility. Obesity also increases the risk of, dyslipidemia (for example, high total cholesterol or high levels of triglycerides), gallbladder disease, osteoarthritis, sleep disorders, respiratory problems, arteriosclerosis and heart failure.
Obesity is the culmination of many underlying mechanisms. Obesity is characterized as uncontrolled adipose tissue mass in the body and recognized as the fastest growing metabolic disorder in the world. An increase in adipose tissue mass can be the result of the production of new fat cells through the process of adipogenesis and/or the deposition of increased amounts of cytoplasmic triglyceride or lipid droplets per cell. In the adipogenesis process, proliferation of preadipocytes or precursor fat cells needs to be followed by the differentiation of these cells to the mature adipocyte phenotype. Increased lipid accumulation in the mature adipocyte cells is the most important feature of obesity disorder. Peroxisome Proliferator-Activator Receptor gamma (PPAR-y) is predominantly expressed in adipocytes and is a key determination factor for adipogenesis.
Fat is stored as triglycerides form in adipose tissue. The breakdown of this fat in fat cells into glycerol and fatty acids is known as lipolysis. During this process, free fatty acids are released into the bloodstream and circulate throughout the body. The hormones such as epinephrine, norepinephrine, glucagon and adrenocorticotropic hormone induce lipolysis. These hormones trigger 7TM receptors, which activate adenylate cyclase. This results in increased production of cAMP, which activates protein kinase A. Protein kinase A subsequently activates lipases found in adipose tissue. It is known that PPAR alpha plays an important role in regulating lipolysis through the control of lipid metabolic enzymes such lipoprotein lipase (LPL). (Ziuozenkova et al., PNAS, Mar. 4, 2003, Vol. 100, no. 5, 2730-2735).
Reducing the formation of new adipose tissue and formation of fat reserves through inhibition of differentiation of pre-adipocytes into mature adipocytes may be a good strategy to control adipogenesis mediated diseases, especially obesity. Modulation of adipogenesis and lipolysis in humans may thus lead to a reduction in the burden of obesity.
The body's adrenergic system plays a major part in regulating energy expenditure and lipolysis. In this process catecholamines mobilize energy-rich lipids by stimulating lipolysis in fat cells and thermogenesis in brown adipose tissue and skeletal muscle. The adrenergic receptor 3 is the principal receptor mediating catecholamine-stimulated thermogenesis in brown adipose tissue, which in humans is distributed about the great vessels in the thorax and abdomen (Thomas, G N, International Journal of Obesity, 545-551, 24, 2000). The 3-adrenergic receptor is also important in mediating the stimulation of lipolysis by catecholamines in the white fat cells of several species, including humans. The brown adipose tissue differs from white adipose tissue in that it has large numbers of mitochondria containing a so-called uncoupling protein, which can stimulate oxidative phosphorylation and thereby increase the metabolic rate (Peter Arner, The β3-Adrenergic Receptor—A Cause and Cure of Obesity? The New England Journal of Medicine, 333: p 382-383). The role of brown adipose tissue is to oxidize lipids to produce heat and rid the body of excess fat. White adipose tissue, which includes subcutaneous and visceral adipose tissue, is much more abundant. It serves to store fat, which can be mobilized by lipolysis to generate free fatty acids for use by other tissues.
Selective agonists of 3-adrenergic receptors are potentially useful in treating obesity because they could enhance energy expenditure with few 1- or 2-adrenergic side effects. A number of 3-adrenergic agonists have been developed and tested experimentally. Hence the treatment with β3-selective agonists can markedly increase energy expenditure and decreases obesity.
Low caloric diets with or without exercise can help with temporary weight loss; however, diet and exercise alone have not proven successful for long-term solutions in weight management (H. G. Preuss, et al., Nutrition Research, 2004, 24, 45-48). In addition, supplementation with drugs that suppress appetite, reduce food intake, reduce dietary fat absorption, increase energy expenditure and effect nutrient partitioning or metabolism have potential efficacy but they are unfortunately accompanied by adverse side effects (C. A. Haller and N. L. Benowitz., New England J. Medicine, 2000, 343, 1833-1838). The pharmaceutical drug, such as phentermine (Fastin, Adipex P), is prescribed for weight control but these have side effects like high blood pressure, headache, insomnia, irritability and nervousness. The other important drugs for weight control are Xenical (Roche Pharm. Co. Ltd., Swiss) and Reductil (Abbot Co. Ltd., USA), which cause gas generation, cramps, diarrhea and elevated blood pressure, common side effects. All these therapies are based on active ingredients that are of synthetic origin.
Effective anti-obese therapies with satisfactory efficacy and acceptable safety have been long overdue. More importantly, anti-obese agents of natural origin with proven safety are greatly needed to control the growing menace. Many herbal and natural products containing gymnema extract, garcinia extract, or carnitine, for example are known to prevent fat accumulation through the inhibition of fat absorption, enhancement of fat decomposition, and the enhancement of fat consumption by the body. It is particularly advantageous for inhibition, amelioration and prevention of obesity if an anti-obesity action can be imparted to food products and beverages, which are ordinarily ingested.
The Piper betle plant is a Piperaceae plant indigenous throughout the Indian Malay region. It is also being cultivated in Madagascar, Bourbon and the West Indies. It is a climbing shrub trained on poles or tall trees as a branching vine. It is generally too tender to grow outside of the tropics.
Piper betle has thousands of years of history in traditional Ayurvedic medicine as treatment for diabetes, cough, digestion and many other ailments (Glossary of Indian Medicinal Plants, pp. 195, 1996). In Indian Subcontinent and East Asian countries Betel leaf is regularly ingested as paan, a popular after meal digestive. The paan is a parcel of Betel leaf wrapped around a mixture of fragrant spices, slaked lime fine shreds of areca nut. Betel leaf and areca nut chewing is a tradition which dates back to thousands of years and the habit has been passed down through the generations and now provides a culture link to their past. Betel leaf and slaked areca nut are commonly used in marriage functions and other important ceremonies in India. Chewing of Betel leaves is also suggested as a remedy for catarrhal and pulmonary disorders.
The chief constituent of the betel leaves is a volatile oil. It mainly produces many phenolic metabolites, called chavibetol, chavicol, hydroxychavicol and eugenol. The inflorescence of Piper betle contains high concentrations (15 mg/g fresh weight) of safrole, an essential oil used in cosmetics and as a food flavoring agent.
Hydroxychavicol suppressed the growth of KB cells in cell media and resulted in cell cycle arrest at late Sand G2/M phase of the cell cycle and induces apoptosis. The Piper betle leaf extract showed protective effect from alcoholic toxicity in the rat brain and ameliorate hepatic marker enzymes and tissue antioxidant status in ethanol-treated Wistar rats (Saravanan R, et. al.; J. Med Food 6:261-265). Piper betle extract showed the ability to scavenge the free radicals involved in initiation and propagation steps of cancer. It exhibited potent antioxidant activity (Rathee J S, et. al.; J Agric Food Chem. 2006; 54(24):9046-54). Ethanolic extract of Piper betle exhibited radio protective property (Bhattacharya, S., et. al., J. Radiation Research, 46(2), 165-171, 2005).
Arambewel et al., showed significant reduction of blood glucose level with oral administration of Piper betle extracts (]. Ethanopharmacology, 102, 239-245, 2005). Oral administration of leaf suspension for 30 days to STZ diabetes rats resulted in significant reduction in blood glucose, glycosylated hemoglobin, decreased activities of liver glucose-6-phosphate and fructose-1,6-bisphosphatase with a concomitant increase in liver hexokinase (Santha Kumar et. al., 1. Medicinal food, 9, 108-112, 2006). Oral administration of 300 mg betel extract per day to rats showed significant hypolipidemic effect (Pharmaceutical biology, 42, 323-327, 2004).
U.S. Pat. No. 6,531,166 describes the effect of Betel leaf water extract on the enhancement of cellular immune response mediated by Th1 helper T-Iymphocytes.
U.S. Pat. No. 6,967,034 describe a new herbal-based composition and method for treatment of CD33+ acute and chronic myeloid leukemia by Piper betle leaf extracts, and to provide a process for the isolation of active fraction from leaves or any other plant parts of Piper betle to treat CD33+ AML and CML with a simplified method of isolation of active components from all plant parts of Piper betle possessing biological activities relevant to the treatment of CD33+ AML and CML.
U.S. Pat. No. 6,531,115 provides an analgesic and refreshing herbal composition useful as dentrifrices, said composition comprising 50-60% wt. of Betel extract (from Piper betle leaves); of one or more group I essential oil selected from Levender officinal, Dementholised oil (ex-Mentha arvensis), Fennel oil and Ocimum gratissimum; one or more group II essential oils and their isolates selected from Ocimum Sanctum, Pulegone (ex. Mentha pulegonium), Carvone (ex. Dill seed) and Menthol (ex. Mentha arvensis); one or more group III essential oils selected from Camphor, turpentine oil, Cedarwood oil and Safrole oil, along with Thymol and preservative/antioxidant, and a process for preparing the composition.
U.S. Pat. No. 7,045,157 describes process of preparation and the use of betel leaf extract to induce IFNγ from human peripheral blood mononuclear cells and as a Th1 type immune modulator.
U.S. Pat. No. 6,413,553 describe a pharmaceutical formulation for blocking 5-lipoxygenase activity, which is useful as a leukotriene synthesis and IL4 inhibitor and as a Th1 immunomodulator comprising an effective amount of a combination of aqueous extracts and lyophilized extracts of Piper betle and Murrya koeniggii, and a method of treating humans for respiratory conditions.
U.S. Pat. No. 6,610,332 relates to method of treating visceral leishmaniasis or kala-azar by administering effective amount of betel leaf extract or lyophilized extract together with or associated with an additive and a composition comprising betel leaf extract with a pharmaceutically acceptable additive.
JPH130685A2 describe an antiallergic agent obtained by formulating an extract extracted with water or an organic solvent from leaves of Piper betle L. and demethyleugenol isolated and purified from the extract as active ingredients.
JP2000290165A2 describes a skin aging inhibitor containing as an active ingredient, the solvent extract of at least one plant selected from the group consisting of Pipturus argenteus (Forst.f.) (Indonesian name: Trembesi), Phyllanthus pulcher (Baill.) M.A. (Indonesian name: Naga buana) and Piper betle L. (Indonesian name: Daunsirih), especially the leaves, stems and barks of the Pipturus argenteus (Forst.f) (Indonesian name: Trembesi), the leaves of the Phyllanthus pulcher (Baill.) M.A. (Indonesian name: Naga buana), and the leaves, whole plant, stems and fruits of the Piper betle L. (Indonesian name: Daunsirih). The skin aging inhibitor is formulated to cosmetics, medicines, quasi drugs, foods and the like to utilize the excellent skin aging-inhibiting action.
U.S. Pat. No. 5,698,199 describes lipolysis acceleration method, which comprises orally administering a thistle-series or pepper-family plant or an extract thereof; or dermatologically applying it by local administration or as a bath medicine composition. The inventors describe the lipolysis activity of Piper nigrum and Piper longum. However, the anti-adipogenic or lypolysis activity of Piper betle has not been investigated/disclosed by the inventors.
W006068777A3 and the equivalent US patent US2006134231 describe topical compositions comprising at least one plant extract selected from the group consisting of Rhinacanthus nasutus, Humulus scandens, Sesbania grandiflora, Amorphophallus campanulatu, Pouzolzia pentandra, and Piper betle and any combinations thereof useful in treating, preventing, ameliorating, reducing and/or eliminating loss of subcutaneous fat in the skin. However, the above application does not mention the treatment for visceral fat. Visceral fat is composed of several adipose depots including mesenteric, epididymal white adipose tissue (EWAT) and perirenal depots. Visceral fat accumulation is associated with increased risk of heart disease and type 2 diabetes.
Similarly none of the other patents, listed above, encompassed the anti-adipogenic activity and lipid accumulation inhibition activities of Piper betle. Therefore, the present inventors have investigated the anti-adipogenic activity of Piper betle extracts and its compositions whose target site of action being visceral fat.
The small twining creeper Dolichos biflorus, popularly known as horse gram, belongs to Papilionaceae family. The small, grayish brown and flattened seeds are called vulavalu in vernacular language in the state of Andhra Pradesh, India. Horse gram is native to most parts of India, and is found at an altitude of about 1000 meters. It has value both as food and fodder. The cooked whole seeds or sprouts of horse gram are consumed by a large population in rural areas of Southern India. A popular regional delicacy made of horse gram in Andhra Pradesh is called vulava charu. Dolichos is described as a herb of mildly heat producing nature. The composition containing dolichos, astragalus, codonopsis, rehmannia, and tortoise shell is used for countering the immune suppression in cancer patients. According to the Oriental Materia Medica, dolichos is also useful for “alcohol intoxication.” In ethnobotany and as a home remedy, it has application for urolithiasis, dysuria, bleeding piles. In patients with oedema, a diuretic effect has been shown. As a home remedy, it has also been used in vaginal bleeding, epistaxis and leucorrhoea. In dysuria, its action is due to its diuretic property. It is also used to reduce crystalluria and to lyse stones. The powdered seeds are used as a poultice to induce sweating.
The administration of D. biflorus to experimental rabbits manifested protection against high fat diet (HFP) induced oxidative stress in different tissues. (Muthu, A K, et. al., Indian J. Pharmacol., 38(2): 131-132, 2006). It also showed lipid lowering effect in experimental rats (Muthu A K, et al., Indian J. Expt. Biol. 43; 522-525, 2005). U.S. Pat. No. 5,916,567 describes an herbal anti-diabetic therapeutic product comprising powdered inner seed of Dolichos biflorus and also the powdered fibrous outer shell of the seed of Dolichos biflorus wherein the product is subjected to radiation for a period of 10-20 minutes.
However, none of the prior art reported or disclosed the anti-adipogenic or lipid accumulation inhibition activity of the extracts or purified fractions derived from the Dolichos biflorus plant, more specifically its application for adipogenesis mediated disorders was not encompassed by the literature.
A selected combination of Piper betle and Dolichos biflorus, for example imparts complementary, but largely separate mechanisms of action in the body. While not wishing to be bound by theory, applicant submits that the benefits of combining the Piper betle and Dolichos biflorus extracts, that has unexpectedly showed synergetic effects, are due, at least in part, to the multiple modes of activity of the composition. The antiadipogenic and pro-lipolytic activities of Dolichos biflorus in combination with antiadipogenic activity of Piper betle offer an effective combination to combat obesity.
It is therefore becomes an object of the present invention to develop herbal compositions for the prevention, maintenance and control of obesity.